Heating apparatus



Jan. 17, 1939. A. K. FOULDS HEATING APPARATUS Filed April 11, 1936 Patented Jan. 17, 1939 UNITED STATES PATENT OFFlCE HEATING APPARATUS Application April 11,

6 Claims.

My invention relates generally to heating systems and more particularly to heating systems for heating water for domestic use.

One of the objects of my invention is toprovide a new and improved heating system in which hot water for domestic use is heated by a furnace in winter and by a second heating means in summer, and to provide a system of this character which is economical in operation.

Another object of my invention is to provide a heating system of the above mentioned character in which heating. of the furnace boiler water by the second heating means is prevented.

The invention consists in an improved heating L. system and combination of parts thereof, to be more fully described hereinafter and the novelty of which will be particularly pointed out and distinctly claimed.

In the accompanying drawing, to be taken as a part of this specification, I have fully and clearly illustrated my invention, in which drawing-- The figure is a diagrammatic View of a heating system embodying my invention.

Referring to the drawing by characters of reference, the numeral l designates in general a heating apparatus or furnace of v the type employed in systems using steam or hot water as the heating medium, the furnace l including a boiler 2 inwhich water is heated and from which the water or steam. is conveyed to radiators (not shown) of the system. Associated with the heatingiapparatus I there is a storage tank 3 for hot water for domestic use, the. storage tank 3 having a conduit or pipe iconnected thereto through which cold water is supplied to the tank and hav-- ing a pipe or conduit 5 through which hot water leaves the tank for domestic use. In the present system the water in the storage tank 3 is heated by the heating apparatus I during the heating season, or when the temperature of the water-in boiler 2 is at, or above a predetermined temperature, and to heat thewater in the storage tank 3 by the heating apparatus .I an indirect heater or heat exchange unit I of any suitable type may be employed.

The indirect heater or heat exchange unit I is disposed externally of the boiler I and includes a tank or container 8 which is connected to the boiler 2- by upper and lower conduits or pipes 9 and I0 respectively. Theupper conduit 9 has one end secured in and to the side wall of the boiler 2,

adjacent the upper end thereof, and has its other end secured in and to the top wall of the heater tank 8: The lower conduit I 0 has one end secured-in and to the-side wall 'of'the boiler 2, ad

1936, Serial No. 73,833 (01. 122 s2) jacent the lower end thereof, and has its other end secured in and to the bottom wall of the heater tank 8. The boiler 2, conduits 9, Ill and tank 8 cooperate to provide a circulatory system through which water from the boiler 2 circulates by gravity.

Disposed in the tank 8 of the heater 1 there is a coiled conduit or pipe H whose upper and lower ends are connected to conduits I2 and I3 which connect the coiled conduit l l to the storage tank 3. One end of the conduit l2 may be secured in and to the side wall of the storage tank 3 at a point adjacent the upper end of the tank, and one end of the conduit l3 may be secured in and to the bottom wall of the storage tank. The coiled conduit H in heater tank 8, the storage tank 3, and the connecting conduits l2 and I3 cooperate to provide a circulatory system for water in tank 3 to circulate to be heated by the boiler water passing through tank 8.

A second heating means such as a gas burning heater I5 is employed for heating the water in the storage tank 3 when the heating apparatus I is not operating, or when it is operating at low fire insufficient to heat the water in tank 3 to the desired temperature. The heater l5 has the usual housing IE enclosing a main burner (not shown) and enclosing a coiled tube or conduit l1 heated by the burner. The upper end of the coiled conduit H is connected to the conduit l2 0f the storage tank circulatory system by a conduit or pipe l8, and the other or lower end of the coiled conduit ll is connected to the lower conduit l3 of the storage tank circulatory system by a conduit or pipe 20. The coiled conduit ll of the heater i5 is thus in parallel with the storage tank 3 and the heater tank 8. A fuel supply conduit or pipe 2! leads to the burner of the heater l5, and in the fuel supply conduit 2|, adjacent the underside of the heater l5, there is preferably provided a manually operable valve 22 for stopping flow of fuel to the burner. The fuel supply conduit 2| extends upwardly adjacent the side wall of the storage tank 3, and connected in the conduit 2| there is a thermostatic valve 23 operable in response to the temperature of the water in storage tank 3 for controlling flow of fuel to the burner of heater l5. The valve 23 comprises in general a casing 24 having a valve port controlled by a valve member 25 which is actuated by a temperature responsive element or bulb 26. The valve casing 24 has an open end disposed toward and secured to the wall of the storage tank 3, the storage tank having an opening in alignment with the open end of the valve casing: and

through which the bulb element 26 projects into the storage tank. The bulb element 26 may be charged with a suitable expansible and contractible fluid responsive to changes in temperature. Preferably a casing 2'! surrounds the bulb element 26 to shield the bulb element from the water in tank 3 and to prevent contamination of the water in tank 3 by the expansible-contractible fluid in the event of a leak developing in the bulb element. Connected to the valve casing 24 on the inlet side thereof is one end of a conduit or tube 30, the other end of the conduit 30 being connected to a constantly burning pilot light (not shown) for lighting the main burner of the heater I5.

In order to prevent the heating of the water in the boiler 2 by the heater l5 and thereby effect a saving in fuel, I provide a temperature responsive device or valve 3| in the conduit I2 of the storage tank circulatory system intermediate coils II and I! for stopping circulation of the water through coil ll with resultant stopping of heat transfer from the water in the storage system to the water in the boiler when the temperature of the boiler Water decreases to a predetermined temperature. The control device 3l includes a temperature responsive element or bulb 32 projecting into the boiler 2, the bulb being connected to the valve casing by a tube or con duit 33. Preferably the bulb 32 is surrounded and enclosed by a casing 34. The bulb 32 may be charged with any suitable eXpansible-contractible fluid responsive to changes in temperature for opening and closing the valve.

The operation of the above described system is as follows: During the heating season when the temperature of the boiler water is above the temperature for which the thermostatic valve 3| is set to close, hot water from the boiler will circulate by gravity through conduit It, tank 8 and conduit 9 and'back to the boiler. Water from the storage tank 3 circulating through the coiled conduit II in heater tank 8 will be heated by the boiler water and thus the Water in tank 3 will be heated. When a low fire is desired in the heating apparatus I, as in the spring or fall of the year, the'temperature of the boiler water may not be suificiently high to heat the water in the storage tank to the temperature desired. When this condition exists the thermostatic valve 23, responsive to the temperature of the water in the storage tank 3, opens to permit flow of gas to the burner of heater IS, the gas being lighted by the constantly burning pilot light. Water in the storage tank 3 then circulates through the coil I! of the gas heater l5 and is heated. However, when the temperature of the boiler water decreases to a temperature insufficient to heat the water in the storage tank to the desired temperature, the thermostatic valve 3l in conduit l2 closes and stops flow of storage tank water through coil I I so that the boiler water is not heated by the gas heater I 5. When the water in the boiler 2 is again increased to the required heater l5.

What I claim and desire to secure by Letters Patent of the United States is:

1. In a heating system, a heating apparatus including a boiler for water to be heated, a storage tank for hot water for domestic use, conduit means cooperating with said storage tank to provide a circulatory system for the water in said tank, second conduit means, said second-named conduit means cooperating with the boiler of said heating apparatus to provide a circulatory system for the boiler water, said circulatory systems having portions thereof in heat exchange relation to heat the storage tank water by said heating apparatus, and a temperature responsive device in said first-named conduit means and operable in response to the temperature of the water in the boiler for controlling circulation of water through said first-named conduit.

2. In a heating system, a heating apparatus including a boiler for water to be heated, a storage tank for hot water for domestic use, conduit means cooperating with said storage tank to provide a circulatory system for the storage tank water, second conduit means, said second-named conduit means cooperating with the boiler of said heating apparatus to provide a circulatory system for the boiler water, said conduit means having portions thereof in heat transfer relation to each other to heat the water in the storage tank by the heating apparatus, a second heating apparatus for heating the water in said storage tank, and a temperature responsive device in said first-named conduit means for controlling flow therethrough, said temperature responsive device being operable in response to a predetermined decrease in boiler Water tempera ture for stopping circulation in said first-named conduit means to prevent the heating of the boiler water by said second-named heating apparatus.

3. In a heating system, a heating apparatus having a boiler wherein Water is heated, a storage tank for hot water for domestic use, conduit means cooperating with said storage tank to provide a circulatory system for the water in said storage tank, conduit means cooperating with the boiler of said heating apparatus to provide a circulatory system for the boiler water, said conduit means having portions thereof in heat transfer relation with each other for heating the water in the storage tank by said heating apparatus, a second heating apparatus for heating the water flowing through said first-named conduit means when the temperature of the boiler water decreases to a predetermined temperature, and a temperature responsive device in said firstnamed conduit means, said temperature responsive device being operable upon a decrease in the boiler water temperature to said predetermined temperature for stopping flow through said firstnamed conduit to prevent heating of the boiler water by said second-named heating apparatus.

4. In a heating system, a heating apparatus including a boiler wherein water is heated, a storage tank for hot Water for domestic use, conduit means cooperating with said storage tank to provide a circulatory system for the circulation of the storage tank water, said conduit means having a portion thereof in heat transfer relation with the boiler Water to heat the water in the storage tank by the heating apparatus, a second heating apparatus, said second-named heating apparatus being connected in said conduit means for heating the water in said storage tank when the temperature of the water in said boiler decreases to a predetermined temperature, temperature responsive means operable in response to the temperature of the water in said storage tank for controlling operation of said secondnamed heating apparatus, and temperature responsive means in said conduit means between said portion and said second-named heating apparatus and responsive to the temperature of the boiler water for controlling flow through said conduit means portion to prevent the heating of the boiler water by said second-named heating apparatus.

5. In a Water heating system, a water storage tank, a heating apparatus including a chamber for a heated liquid medium, a heat exchange device having a pipe coil positioned in said chamber, conduit members communicatively connecting the ends of said pipe coil and the interior of said storage tank, an auxiliary heating means for heating the storage tank water, a conduit member having a portion subject to the temperature of said auxiliary means and having its ends communicatively connected with the interior of said storage tank at different levels so that the storage tank water may be heated by said auxiliary means, a valve for stopping flow through said coil, and means responsive to temperature of said liquid medium to maintain said valve in open position when the temperature of said liquid medium is above a predetermined temperature.

6. In a water heating system, a Water storage tank, a heating apparatus including a chamber for a heated liquid medium, a heat exchange device having a pipe coil positioned in said chamber, conduit members communioatively connecting the ends of said pipe coil and the interior of said storage tank, an auxiliary heating means for heating the storage tank water, a conduit member by-passing said pipe coil and connected to said conduit members and subject to the temperature of said auxiliary means so that the storage tank water may be heated by said auxiliary means, a valve for stopping flow through said coil, and means responsive to temperature of said liquid medium to maintain said valve in open position when the temperature of said liquid medium is above a predetermined temperature.

ANDREW K. FOULDS, 

